Furnace roof block



Sept. 14, 1965 Filed May 18, 1962 FIGI FIG?

A. A. USMIANI FURNACE .ROOF BLOCK 2 Sheets-Sheet 1 A TTORNE Y S Sept. 14, 1965 A. A. UsMlANl 3,205,842

FURNACE VROOF BLOCK Filed May 18, 1962 2 Sheets-Sheet 2 FI G 6 INVENOR.

ANDREW A. USMIANI A TTORNE YS United States Patent O 3,205,842 FURNACE ROOF BLOCK Andrew Anthony Usmiani, Hollywood, Fla., assignor to National Steel Corporation, a corporation of Delaware Filed May 18, 1962, Ser. No. 195,824 9 Claims. (Cl. 110-99) The present invention relates to furnace roof blocks, more particularly of the type comprising a metal-sheathed refractory brick. A

It has long been known to form the roofs of furnaces from blocks or bricks of refractory material. Originally, these blocks were comprised entirely of refractory material, the refractory material of one block contacting the refractory material of the next adjacent block. Such blocks, however, suffered from several disadvantages. In the first place, there was no efcient way to seal between the bricks forming the roof, so that heat and gases escaped between the blocks. In the second place, the exposed refractory blocks were subject to damage during shipment and installation.

More recently, furnace roof blocks of the refractory brick type have been encased in metal sheathing about their sides, so that the above difficulties are overcome. In the first place, the metal-to-metal contact of the sheathing of adjacent bricks assures that the contacting metal surfaces will oxide and bond together under the influence of the furnace heat, thereby to seal between adjacent blocks. In the second place, the metal sheathing protects the bricks during shipment and installation so that the roof blocks are largely safe from damage.

Furnace roofs as heretofore known have generally been arched, but have sometimes been flat. Arched roofs are usually installed in one of two ways: either the individual blocks are held by hangers that support the blocks from the fixed supporting structure of the furnace, or else the blocks support each other on the arch principle, that is, the side walls of adjacent blocks press against each other in such a way as to retain all the blocks in the configuration of an arch. Flat roofs, which cannot take advantage of the arch principle, have heretofore been supported by hangers.

Serious problems arise, however, when it is attempted to install a roof of any of the types described above. In the case of flat or arched roofs supported by hangers, it has ordinarily been necessary heretofore to provide a hanger for each block, as in U.S. Patent No. 2,997,008. Arrangements have been proposed for supporting a plurality of blocks from a single hanger, as in U.S. Patent No. 2,187,669. In each case, however, it has ordinarily been necessary to provide hanger construction contacting each block, so that the installation and replacement of an individual block inevitably entails manipulation of this hanger structure by which the block was supported from fixed supporting structure of the furnace. The manner of installation and repair of arched roofs has been somewhat different from that of at roofs in that the use of hangers for arched roofs can sometimes be avoided. Even so, in this latter case, it has been necessary to provide a form of scaffolding or support for the arch until the heat of the furnace caused the metal sheathing to oxidize so that the arch became a unitary whole, and this is true not only of the arch during initial construction but also of the arch during repair as by replacement of individual blocks.

During the course of the replacement of an individually suspended block, it is necessary, in the case of a roof in which all the blocks are supported by hangers, to manipulate the hanger of the block to be removed in a rather cumbersome way, and similarly to manipulate the hanger with respect to the block that replaces the removed block. In the case of an arched roof without hanger support,

it has been necessary to provide special support for an individually replaced block until such time as the furnace heat integrates the new block with the previous blocks, at least when a plurality of contiguous blocks were simultaneously installed or replaced.

The present invention solves the foregoing problems by providing furnace roof block structure in the form of a metal-sheathed refractory brick, characterized by a hook that extends downwardly and outwardly from an upper edge of one side of the metal sheathing, whereby a hook integral with one side 'of the metal sheathing attaches over and is supported 0n an upper edge portion of the metal sheathing on the other side of the adjacent refractory brick.

Accordingly, it is an object of the present invention to provide furnace roof blocks that enable the construction of a new furnace roof with no special supporting structure.

Another object of the present invention is the provision of furnace roof blocks that can be individually replaced with no special fittings or attachments, during the course of repairing a furnace roof.

Finally, it is an object of the present invention to provide furnace roof blocks which will be relatively simple and inexpensive to manufacture, easy to install, maintain and replace, and rugged and durable in use.

Other objects and advantages of the present invention will become apparent from a consideration of the following description, taken in connection with the accompanying drawings, in which:

FIGURE l is an elevational view, with parts in cross section, showing furnace roof blocks according to the present invention in one of the environments in which they may be used;

FIGURE 2 is an enlarged fragment of FIGURE 1, showing how furnace roof blocks according to the present invention may be suspended from the furnace roof supporting structure;

FIGURE 3 is a perspective view of one embodiment of furnace roof block according to the present invention;

FIGURE 4 is another enlarged fragment of FIGURE 1, showing furnace roof blocks according to the embodiment of FIGURE 3;

FIGURE 5 is a view similar to FIGURE 4, but showing a modified form of furnace roof block according to the present invention;

FIGURE 6 is a view similar to FIGURES 4 and 5, but showing still another modification of furnace roof blocks according to the present invention; and

FIGURE 7 is a view similar to FIGURE l, but showing furnace roof blocks according to the present invention in a somewhat different environment.

Referring now to the drawings in greater detail, there is shown in FIGURE 1 a furnace roof including a plurality of parallel supporting beams 1, only one'of which is shown. Beams 1 on their upper surfaces supporta plurality of rods 3, only one of which is shown, which extend transversely of the length of beams l. Each of rods 3, in turn, supports a plurality of inverted U-shaped hangers 5 spaced apart along the length of rod 3 and having downwardly extending legs from the lower end of each of which is suspended a furnace roof block f7.

Suspended roof blocks 7 are each comprised of a brick 9 of conventional refractory material, encompassed on all four sides, but not on its `top or bottom, by a metal case or sheathing 11. Brick 9 is recessed as at 13 adjacent the central portion of the upper edge of one side of metal sheathing 11, and a tab 15 formed from the material of sheathing l1 and of a width substantially less than the width of the roof block is disposed centrally of its associated side of the upper edge of the metal sheathing and extends inward into the recess at 13. Tab 15 has au simultaneously.

3 upwardly inwardly extending diagonal section 17 which terminates upward in a vertical section 19, which in turn terminates upward in a hook 21 that is bent over and extends downward and outward from adjacent the level of the upper edge of metal sheathing 11 and that engages through a slot in the lower end of a leg of hanger 5. Hook 21, however, is disposed on the same side of the plane of the adjacent side of sheathing 11 as is brick 9.

Suspended roof block 7 has a notch 23 in the upper edge of that side of metal sheathing 11 which is opposite the side of the metal sheathing from which tab 15 is formed. Like tab 15, notch 23 is disposed centrally of its associated upper edge of the metal sheathing. Notch 23, however, is rather shallow and is of a depth about equal to the thickness of metal sheathing 11. The lower edge of notch 23 is disposed at a level substantially above the lower end of hook 21.

There are two varieties of furnace roof block that are used in the course of the present invention, and these are not alternative to each other. Instead, they are used The first type is the suspended roof block 7, characterized by tab 15. The second type is a supported furnace roof block shown in some of its many possible forms in FIGURES 3-6. In FIGURE 3, for

example, there is shown a supported furnace roof block 25 which comprises a brick 27 of conventional refractory `1naterial encased by a metal casing or sheathing 29.

vSupported roof blocks 25 are supported in the sense that they are not individually suspended as are suspended blocks 7 and as were furnace roof blocks according to the prior art. Instead, blocks25 are supported on other 'furnace roof blocks; and for this purpose, one side 31 'of metal sheathing 29 of each block 25 terminates upward in a hook 33 which extends from the upper edge of side 31 outward and downward and terminates a substantial distance below the upper edge of side 31. Hook 33' is integral with side 31 and may be formed by bending over a tab of appropriate size in the form of a hook. Hook 33 extends along side 31 a distance substantially less thanl the width of side 31 and is disposed centrally of the upper edge of side 31. Needless to say, in addition to the formation of hook 33 by bending a tab, hook 33 could also be formed by welding or riveting a member to the upper edge portion of side 31, in which latter cases hook 33 would still be integral with side 31 within the meaning-of the present invention. It should also be noted that hook 33, unlike tab 15, is disposed on that side of the upright plane of side 31 that is opposite brick 27. Thus, hook 33 projects laterally outward beyond the plane of its associated side, while hook 21 is recessed into its v associated block.

The side 35 of metal sheathing 29 opposite hook 33 is provided at its upper edge with a downwardly extending shallow notch 37'of an extent lengthwise of the upper 'edge of the side 35 substantially less than the length of that edge. Like hook 33, notch 37 is centered between the ends of its associated upper edge, and is of an extent lengthwise of that edge substantially greater than the lengthwise extent of hook 33. Brick 27 adjacent notch 37 is recessed as at 39 to a length about equal to the length of notch 37, as best seen by comparison with FIGURES 3 and 4. Bottom edge 41 of notch 37 is disposed a substantial distance above the bottom of the brick recess at 39, and bottom edge 41 provides in effect a continuation of the upper edge of side 35, albeit at a different level from other portions of that upper side edge.

In use, the supported blocks 25 are merely hung one on the other and on suspended blocks 7. This is done by Vdisposing hook 33 in a notch 23 or 37. The upper inner surface of hook 33 being at about the same level as the bottom edge of notch 23 or bottom edge 41 of notch 37, the supported blocks 25 assume the same level as each other and the same level as suspended blocks 7. As seen in FIGURE l, therefore, hangers suspend blocks 7; but each block 7 supports at least one block 25, and

in the preferred form several blocks 25. In the illustrated embodiment, each suspended block 7 supports three supported blocks 25, the block 25 adjacent block 7 in turn supporting two of these blocks, and the next block in turn supporting one of these blocks.

The method of assembly, therefore, of a furnace roof according to FIGURE l is to place hanger 5 over rod 3 and then to suspend two blocks 7 in confronting relationship from the slots in the lower ends of the legs of hanger 5, and then to add supported blocks 25 progressively by hooking them one over the other until the desired number of blocks is achieved, whereupon another rod 3 (not shown) can be fitted with another hanger 5 and so on to the right or left of the structure shown in FIGURE l. It is also to be understood that there will be a plurality of hangers 5 spaced apart lengthwise of each rod 3 by an interval corresponding to approximately the width of a block 7 or 25 as measured parallel to rod 3, and that further courses of blocks will be assembled above and below the plane of FIGURE l. Moreover, it will be understood that the present invention is equally well adapted for use in the construction of fiat or arched roofs, the practice of the invention in connection with arched roofs making it necessary only to impart a slight wedge shape to the blocks in a manner well known in this art.

In FIGURE 5 there is shown another embodiment of roof block according to the present invention, in which the brick 27 instead of 4being recessed as was brick 27 in the preceding embodiment, does not extend full height of the metal sheathing. Thus, methal sheathing 29' extends upward a substantial distance beyond the fiat horizontal upper surface of brick 27', and the hook 33' at the upper edge of side 31 terminates `downward in a lower end that is spaced above the upper surface of brick 27. Similarly, the opposite side 35 of the metal sheathing of the embodiment of FIGURE 5 carries at its upper edge a notch for the reception of hook 33', this notch being spaced a substantial distance above the upper surface of brick 27.

Still another embodiment of roof block according to the present invention is shown in FIGURE 6, in which the hook 33 is formed from the material of the metal sheathing that would otherwise have a plain upper edge. To this end, the metal sheathing of the embodiment of FIGURE 6 is slotted downward from its upper edge a distance equal to the length of hook 33, whereupon the remaining upstanding tab is bent over to form hook 33". The corresponding notch 37 on the other side of the blocks, which receives vhook 33, is correspondingly deeper. Moreover, brick 27" is provided with a correspondingly deeper recess 39" for the reception of the deeper hook assembly. v

It will also be understood that the bottom edges of notches 23 or 37 may also be bent over in the same direction as hook 33 in any of the illustrated embodiments, so as to avoid resting hook 33 on a sharp edge. Additionally, the lengthwise extent of the notch will always be substantially greater than the lengthwise extent of its associated hook.

Another embodiment of the environment in which any of the illustrated embodiments of roof blocks according to the present invention may be used is shown in FIG- URE 7, in which the beams 1 and rods 3 are replaced by ribs 43 disposed in parallel vertical planes and comprising the fixed supporting structure of the furnace roof. In this latter case, hangers 45 suspend blocks 7 from ribs 43 by means of hooks 47 at the upper ends of hangers 45. At the lower ends, hangers 45 have the same slots as would hangers 5, for the reception of hooks 21 of tabs 15 on the metal sheathing of blocks 7. As also in the case of FIGURE l, supported blocks 25 are hung on each suspended block 7, the ribs 43 being spaced apart distances that are multiples of the width of blocks 7 and 25. For this purpose, in each of the embodiments of FIG- URES l and 7, it is preferred that rods 3 and ribs 43 be` placed by hanger of FIGURE l, in which case the roof would be built outward in both directions from each rib 43 and the number of ribs 43 could be reduced by half. Similarly, hanger 5 in FIGURE 1 could be replaced by hanger 45 of FIGURE 7, in which case the number of rods 3 of FIGURE 1 would be doubled and the blocks would be installed in one direction only.

To repair a furnace roof comprised of blocks according to the present invention, by replacement of an individual block, it is necessary only to remove those blocks that are supported by the block to be replaced, and then to remove the block to be replaced. Alternatively, of course, the block to be replaced can be removed at the same time as the blocks supported thereby, and the block to be replaced can thereafter be separated from the blocks it supports. In any event, a new or repaired block is then reinstalled simply by hanging one block on another as in the original construction of the roof, until the end of that group of blocks is reached. Thus, in no case of the replacement of an individual block is it necessary to remove more than several blocks; and the removal and replacement of these blocks are quite easy and can be performed without any supporting structure or scatfolding. A roof construction of blocks according to the present invention is thus self-supporting as installed and needs no special supports to hold it up until portions of the metal sheathing of adjacent blocks in contact with each other have integrated by oxidation.

From a consideration of the foregoing disclosure, it will be obvious that all of the initially recited objects of the present invention have been achieved.

Although the present invention has been described and illustrated in connection with preferred embodiments, it is to be understood that modifications and variations may be resorted to without departing from the spirit of the invention, as those skilled in this art will readily understand. Such modifications and variations are considered to be within the purview and scope of the present invention as defined by the appended claims.

What is claimed is:

1. A furnace roof block comprising a refractory brick and metal sheathing covering at least a pair of opposite sides of the brick and secured to the brick to support the brick, a portion of an uppermost part of the sheathing on one of said pair of opposite sides of the brick -being in the form of an integral outwardly and downwardly extending hook that terminates downwardly at a level lower than the level of the directly opposed upper edge of the sheathing on the other of said pair of opposite sides of the brick, said directly opposed portion of the edge of the sheathing being free standing and being the bottom edge of a notch of a width substantially greater than the width of the hook.

2. A pair of furnace roof blocks each comprising a refractory brick, and metal sheathing covering at least a pair of opposite sides of each brick and secured to each brick to support the brick, a portion of an uppermost part of the sheathing on one of said pair of opposite sides of each brick being in the form of an integral outwardly and downwardly extending hook that terminates downwardly at a level lower than the level of the directly opposed upper edge of the sheathing on the other of said pair of opposite Isides of each brick, said directly opposed upper edge being free standing, the hook on one said block resting over and supporting said one block on said directly opposed upper edge of the sheathing of the other said block, said directly opposed portion of the upper edge of the sheathing of said other block being the bottom edge of a notch of a width substantially greater than the width of the hook of said one block, the hook of said one block being disposed in said notch.

3.. A pair of furnace roof blocks as claimed in claim 2,

6 the sheathing adjacent the hook of the other said block being disposed in a generally upright plane, the hook of the other said block lying on the side of said plane opposite the brick of said one block.

4. A pair of furnace roof blocks as claimed in claim 2, the sheathing of said other block extending upwardly a substantial distance beyond the brick of said other block, the hook of said one block terminating downwardly no lower than the level of the brick of said other block.

5. A pair of furnace roof blocks as claimed in claim 2, the brick of said other block being recessed adjacent said directly opposed upper edge of the sheathing of said other block, the hook of said one block terminating downwardly substantially lower than the uppermost portion of the brick of said other block.

6. A set of at least three serially connected furnace roof blocks, each comprising a refractory brick, and metal sheathing covering at least a pair of opposite sides of each brick and secured to each brick to support the brick, a portion of an uppermost part of the sheathing on one of said pair of opposite sides of each brick being in the form of an integral, outwardly and downwardly extending hook, at least two of said hooks terminating downwardly at a level lower than the level of the directly opposed upper edge of the sheathing on the other of said pair of opposite sides of each brick, the hook on at least two of said blocks resting over the directly opposed upper edge of the sheathing of a serially connected block, said directly opposed upper edge being free standing, said hook and upper edge connections being the sole connections for at least one of said blocks, whereby two blocks can independently support an intermediate block, and the directly opposed upper edge of the sheathing is the bottom edge of a notch of a width substantially greater than the width of the hook disposed in said notch.

7. The set of at least three serially connected furnace roof blocks as defined in claim 6, where in at least one of said blocks the sheathing adjacent the hook is disposed in a generally upright plane, and the hook lies on the side of said plane opposite the brick of said at least one block.

8. The set of at least three serially connected furnace roof blocks as defined in claim 6,.the sheathing of at least one block extending upwardly a substantial distance beyond the brick of the serially connected block, the hook of said at least one block terminating downwardly no lower than the level of the brick of the serially connected block.

9. The set of at least three serially connected furnace roof blocks as defined in claim 6, the brick of at least one block being recessed adjacent said directly opposed upper edge of the sheathing of a serially connected block, the hook of said at least one block terminating downwardly subsantaially lower than the uppermost portion of the brick of the serially connected block.

References Cited by the Examiner UNITED STATES PATENTS 1,285,051 11/18 Cramer 50-446 X 1,440,446 1/ 23 Cotton 50-397 X 2,158,759 5/39 Morlock 110-99 2,476,423 7/ 49 Longenecker l 10-99 2,781,006 2/57 Heuer 110-99 2,846,963 8/58 Mason et al. 11G-99 2,885,976 5/59 McGill et al 110-99 3,004,302 10/ 61 Nightingale 50-61 X 3,005,424 10/ 61 Heuer 110-99 3,068,813 12/62 Walt 110-99 3,073,264 l/ 63 Monlux 11G-99 OTHER REFERENCES German Printed Application No. 1,114,971, 10/61.

JAMES W. WESTHAVER, Primary Examiner.

FREDERICK KETTERER, Examiner. 

6. A SET OF AT LEAST THREE SERIALLY CONNECTED FURNACE ROOF BLOCKS, EACH COMPRISING A REFRACTORY BRICK, AND METAL SHEATHING COVERING AT LEAST A PAIR OF OPPOSITE SIDES OF EACH BRICK AND SECURED TO EACH BRICK TO SUPPORT THE BRICK, A PORTION OF AN UPPERMOST PART OF THE SHEATHING ON ONE OF SAID PAIR OF OPPOSITE SIDES OF EACH BRICK BEING IN THE FORM OF AN INTEGRAL, OUTWARDLY AND DOWNWARDLY EXTENDING HOOK, AT LEAST TWO OF SAID HOOKS TERMINATING DOWNWARDLY AT A LEVEL LOWER THAN THE LEVEL OF THE DIRECTLY OPPOSED UPPER EDGE OF THE SHEATING ON THE OTHER OF SAID PAIR OF OPPOSITE SIDE OF EACH BRICK, THE HOOK ON AT LEAST TWO OF SAID BLOCKS RESTING OVER THE DIRECTLY OPPOSED UPPER EDGE OF THE SHEATING OF S SERIALLY CONNECTED BLOCK, SAID DIRECTLY OPPOSED UPPER EDGE BEING FREE STANDING, SAID HOOK AND UPPER EDGE CONNECTIONS BEING THE SOLE CONNECTIONS FOR AT LEAST ONE OF SAID BLOCKS, WHEREBY TWO BLOCKS CAN INDEPENDENTLY SUPPORT AN INTERMEDIATE BLOCK, AND THE DIRECTLY OPPOSED UPPER EDGE OF THE SHEATING IS THE BOTTOM EDGE OF A NOTCH OF A WIDTH SUBSTANTIALLY GREATER THAN THE WIDTH OF THE HOOK DISPOSED IN SAID NOTCH. 